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Demosaicing Method for Digital Cameras with White-RGB Color Filter Array

  • Park, Jongjoo (Department of Electronics Engineering, Hanyang University) ;
  • Jang, Euee Seon (Division of Computer Science & Engineering, Hanyang University) ;
  • Chong, Jong-Wha (Department of Electronics Engineering, Hanyang University)
  • Received : 2014.11.27
  • Accepted : 2015.10.14
  • Published : 2016.02.01

Abstract

Demosaicing, or color filter array (CFA) interpolation, estimates missing color channels of raw mosaiced images from a CFA to reproduce full-color images. It is an essential process for single-sensor digital cameras with CFAs. In this paper, a new demosaicing method for digital cameras with Bayer-like W-RGB CFAs is proposed. To preserve the edge structure when reproducing full-color images, we propose an edge direction-adaptive method using color difference estimation between different channels, which can be applied to practical digital camera use. To evaluate the performance of the proposed method in terms of CPSNR, FSIM, and S-CIELAB color distance measures, we perform simulations on sets of mosaiced images captured by an actual prototype digital camera with a Bayer-like W-RGB CFA. The simulation results show that the proposed method demosaics better than a conventional one by approximately +22.4% CPSNR, +0.9% FSIM, and +36.7% S-CIELAB distance.

Acknowledgement

Supported by : IITP (Institute for Information & Communications Technology Promotion)

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